7.3 magnitude earthquake damages US Embassy in Vanuatu

LONDON -- The U.S. Embassy in Port Vila was damaged on Tuesday as a 7.3-magnitude earthquake struck the South Pacific island nation of Vanuatu.

The earthquake struck about 18 miles west of the capital just before 1 p.m. local time, the U.S. Geological Survey said. A series of aftershocks followed, but no tsunami warnings were issued.

The embassy, which is in the capital on the island of Efate, "sustained considerable damage during the earthquake and is closed until further notice," U.S. officials said in an alert. All staffers who were in the building at the time of the quake were safe and accounted for, officials said in a later update on social media.

"Our thoughts are with everyone affected by this earthquake, and the U.S. government will work closely with our partners in Vanuatu," the update said.

Michael Thompson, an Australian national who owns Vanuatu Jungle Zipline in Port Vila, told ABC News that he hadn't experienced an earthquake as strong as Tuesday's in his two decades in the country.

Roads were impassable, meaning Thompson was unable to travel to reach his wife at home, he said.

"There's been an enormous amount of ground movement, you can see splits through buildings, cranes upended, 20-30-ton rocks lying by the road," he said.

There were reports of landslides in the Port Vila area, the embassy said. Thompson added that rescuers had told him that, without equipment, they had not yet been able to free people trapped in the rubble in the center of Port Vila. "I could still hear their screams, there's just no way to extricate them," he said.

"People are advised to avoid entering buildings as they may be damaged or unstable," the embassy's alert said.

ABC News' Joe Simonetti contributed to this report.